1. Field of the Invention
The present invention relates to a cooling fan, and more particularly to a cooling fan having improved stationary blades.
2. Description of Related Art
With continuing developments in electronic technology, electronic packages such as CPUs (central processing units) generate increasing amounts of heat that requires immediate dissipation. Cooling fans are commonly used in combination with heat sinks for cooling such CPUs.
Normally, a cooling fan includes a stator and a rotor. The rotor includes a hub and a magnet arranged in the hub and surrounding the stator, which includes a stator core with coils wound therearound. When electrical currents are supplied to the coils, the rotor is rotated by magnetic force of the coils and fan blades of the rotor produce forced airflow. A hollow frame supports the rotor and the stator thereon. A columnar supporting base is formed in a center of the frame, and a number of ribs interconnect the supporting base and the frame. Unfortunately, when airflow exits the frame, turbulent flow is generated after the airflow encounters the ribs, having an adverse effect on air flow and reducing operating efficiency of the fan.
For the foregoing reasons, therefore, there is a need in the art for a cooling fan which overcomes the described limitations.